package chapter7;

/**
 * @author lzy
 * @version v1.0
 * Create DateTime: 2019/3/7 17:20
 */
public class SpaceShipControls {
    void up(int velocity) {

    }

    void down(int velocity) {

    }

    void left(int velocity) {

    }

    void right(int velocity) {

    }

    void forward(int velocity) {

    }

    void backward(int velocity) {

    }
}
